I have been holding off on this until I gathered more data. I wish my Core numbers were as good as yours. I try to stick with data and avoid emotion, so here is my attempt.
ENVIRONMENT: I fly at the Willy McCool Park in North Las Vegas Nevada, please google map it and note our proximity to a very large housing subdivision. There is also a large cell tower located approximately 1.5 miles from our field. Nellis Air Force Base, home of Red Flag, the Weapons School and the Thunderbirds, is 10 miles away. The Nellis air combat ranges are to the North of us on the other side of 8000 ft mountains.
PERSONAL FLYING HISTORY: I have flown RC at this field since 2005 and NEVER had an RF issue using a JR 12X on both DSM2 and DSMX. I fly jets and Warbirds (BVM F-4 and CARF Corsair for example). I have flown RC since I learned to fly in Germany in 1977. I started flying with the Core last year in October.
THE TEST: Two aircraft, a Yellow Aircraft P-47 with a gas motor and a Black Horse Westland Wyvern on electric. Both aircraft have a PBR9 and PBR26 feeding into a Power Expander on the P-47 and a Mercury on the Wyvern. What follows are the averages for 19 flights between these aircraft:
|19 Flights Total||Low||High||Average|
|Mercury/Expander Lost Frames||63||1076||258|
|PBR9 Min LQ1%||6||65||28|
|PBR9 Min LQ2% (13 of the sample [P-47] have this antenna outside the fuselage)||5||54||21|
|PBR26 Min LQ1% (6 of the sample [Wyvern] have both antennas outside the fuselage in a wing tip)||5||66||41|
|PBR26 Min LQ2%||3||45||59|
|Mercury/Expander Antenna 1 Fades||314||1450||810|
|Mercury/Expander Antenna 2 Fades||319||1018||648|
|PBR9 Frame Losses||397||1152||355|
|PBR26 Frame Losses||245||879||342|
DATA INTERPRETATION: Always flying with 4 receivers at my field is a good plan. The Power Box lost frame average of 258 and 0 holds demonstrates this to me. In this small sample size I see no value in routing the receiver antennas outside the fuselage (one fiberglass, one wood, no carbon fiber). Even the small sample size of 19 confirms what we already know at my field. There are two "hot spots" at either end of the flying area near the houses and in the line-of-sight to the cell tower where Jeti, Futaba MZ18WC and yes...Core, experience serious degraded RF performance. My two jet flyer friends on Jeti use 900 MHz backup and their radios will switch to 900 MHz for a short period of time (less than 5 seconds) when they fly in the "hot spots" on a bad RF day. My Core LQ warnings (set at 10% red and 20% yellow) will also go off if I fly in the same area. I know, 10% and 20%!!! Yes, look at my low and high LQ values. Yes, I account for transmitter proximity to the receivers during preflight
SUMMATION: I do have confidence in the Core, but only with 4 receivers when flying at my field. For me, it is mandatory to have 4 paths for the signal to get through so up to 3 of them can be severely degraded leaving 1 to hold the line for the second or so it takes for one of the other receivers to pick up the load. I have thought about why my Spektrum-based JR12X has never had any issues and I think it is a combination of 1. Always using 4 receivers, so I'm probably not aware its having RF issues, and 2. The older radios like the 12X are pushing 128 milliwatts, I do not have the brain power to know if this is a reasonable assumption.
I have offered this for your information only. Perhaps to steady anyone who is maybe having thoughts about how reliable the Core RF link is. I trust it, and it is going in my new CARF Corsair/Moki combination.